1. Field of the Invention
The hydraulic well cap of the present invention comprises apparatus for capping a well having a pipe stem through which fluid is flowing uncontrollably, such as a gas well or an oil well.
2. Description of the Prior Art
Problems stemming from the uncontrolled flow from oil and gas wells have long been appreciated by those working in the well supply equipment field. The loss of valuable fluid, the contamination of the surrounding environment, and the damage to supporting the equipment all have prompted the development of various devices and techniques for attempting to cap such wells. The potential flammability of the issuing fluid as well as the high fluid velocity make exceedingly dangerous and often impossible as the use of conventional procedures and equipment for securing capping apparatus to the well stem, often necessitating remote control operation. These problems are, of course, compounded if the location of the blowing well is on the ocean floor.
Prior attempts to solve this problem have included apparatus such as shown in U.S. Pat. No. 4,192,376 that is intended to be guided over the flowing type stem whereupon the force of the fluid would act to seat and engage a clamping device and then activate a valve mechanism to finally shut off the flowing well. The principal difficulties in the use of such devices is that they lack the ability to provide a positive coupling and sealing engagement between the pipe stem end and the capping apparatus. Failure to achieve complete engagement between the pipe stem and the capping apparatus can result in an unacceptable rate of leakage and the possibility of the capping apparatus being "blown off" of the well stem when the valve component of the apparatus is activated to shut off the flow, due to the tremendous fluid pressures in the subterranean fluid reservoir and the inertial forces of the high velocity fluid in the pipe stem.